Clearing the Smog

News Articles05/05/2004

Mechanics at AC Transit’s Central Maintenance Division are getting hands-on guidance from the experts at Cummins West, Inc., on how to retrofit buses with a new engine exhaust system that is certified to be effective in reducing unwanted emissions.

Called Cleaire Longview, this exhaust gas recirculation (EGR) kit with particulate trap further cleans emissions from engines that already meet standards imposed in recent years. The kit reduces nitrogen-oxide (NOx, a contributor to smog) emissions by recirculating exhaust gas into the intake air stream. Particulate traps help by cleansing the exhaust stream and ensuring that recirculated gases do not increase engine wear.

This retrofit program is financed by a federal grant approved by the Metropolitan Transportation Commission (MTC), which notes that the California Air Resources Board has verified the effectiveness of the kits. MTC is funding several hundred kits for the District this year and maybe more in 2005.

The Cleaire Longview kit is now on the road in various District buses, including NABI low-floor coaches, a NABI high-floor model and an MCI. Crews presently are engineering the Cleaire installations for the 40-and 60-foot Van Hool coaches.